(1) Field of the Invention
This invention relates to a scheduling method and program for a substrate treating apparatus that performs predetermined treatment such as cleaning, etching and drying on semiconductor wafers or glass substrates for liquid crystal displays (which will be referred to hereinafter simply as substrates).
(2) Description of the Related Art
In treating a plurality of lots with a substrate treating apparatus having a plurality of treating sections, a conventional method of this type, for example, causes a controller to determine beforehand, based on a recipe including a plurality of treating steps, an order of treating a plurality of lots successively in the treating sections. The lots are transported and treated successively according to a schedule prepared in this way.
Specifically, based on a systematic chart showing combinations according to procedures in varied treating steps for each lot, a first treating step for one of the lots is allocated first. Then, following the systematic chart on the basis of that treating step, the next treating step to be selected from among next treating steps for the lots is a treating step for a lot having an earliest expected completion time of all preceding treating steps (see Japanese Unexamined Patent Publications No. 2003-241818 and No. 2003-243274, for example).
The above scheduling method for a substrate treating apparatus determines, before actually starting treatment of the lots, which lot is to be treated in which treating section at which time. Thus, different treating steps for the lots can be allocated efficiently, to improve the operating rate of the substrate treating apparatus.
In order to deal with a case of taking a long time in the schedule preparation as noted above, a comparison is made between a time consumed in the schedule preparation and a predetermined reference time. When the reference time is exceeded, a predetermined time is added to the reference time to make a new reference time. In this way, even when a schedule preparation takes a long time, a scheduling completion time will not be later than a scheduled time (see Japanese Patent No. 3712370).
The conventional method noted above has the following drawback.
In the conventional scheduling method for a substrate treating apparatus, a long time may be required for schedule preparation when an attempt is made to improve the operating rate of the apparatus by reducing standby periods. Problems arising from the long scheduling time may be avoided only by moving back the positions of subsequent treating steps to be allocated. But this will result only in an increase in standby time to inhibit improved operating rate. The lots for scheduling will decrease in number, and hence a problem of a flexible schedule preparation becoming impossible. There is also a problem that the reduced number of lots for scheduling will lower the operating rate.